Control system for a dozer blade

ABSTRACT

A control system for a dozer blade or the like incorporating valving for combining with a tilt control for the blade tilt motors and hydraulic circuitry for the lift motors to additionally provide blade pitch control. Also disclosed is a ball and socket connection for connecting the dozer blade to the dozer frame.

United States Patent Frisbee 1 Feb. 29, 1972 [54] CONTROL SYSTEM FOR A DOZER 2,753,638 7/1956 Mork ..172/803 BLADE 2,766,536 10/1956 Perkins ..172/805 3,175,315 3/1965 Strader ..172/805 [72] Inventor. Claude M. Frisbee, Burlington, Iowa 3,184,869 5/1965 Olsen... "min/803 [73] Assignee: J. 1. Case Company, Racine, Wis. 3,246,406 4/1966 Ray ..172l804 [22] Wed: 1969 Primary Examiner-Robert E. Pulfrey [21] Appl. No.: 874,303 Assistant Examiner-Stephen C. Pellegrino Attorney-Cullen, Settle, Sloman & Cantor [52] US. Cl... ..172/804, 172/805 51 rm. (:1. .1202! 3/76 [571 ABSTRACT Fleld of Search A control System for a dozer or the incorporating 60/595 valving for combining with a tilt control for the blade tilt motors and hydraulic circuitry for the lift motors to additionally [56] References cued provide blade pitch control. Also disclosed is a ball and socket UNITED STATES PATENTS connection for connecting the dozer blade to the dozer frame.

2,730,823 1/1956 Cassidy 172/805 5 Claims, 6 Drawing Figures PATENTEnriazs @972 3,645,340

SHEET 1 OF 3 I NVENTOR.

CLAUDE M. FRISBEE.

CULLEN, SETTLE, SLOMAN 8 CANTOR PAIENIEnriaze i912 3. 645 340 SHEET 2 (IF 3 INVENTOR.

CLAUDE M. FRISBEE.

CULLEMETTLE, -iOMAN 8 CANTOR.

ATT'YS.

CONTROL SYSTEM FOR A DOZER BLADE This invention relates to improvements in dozer blade controls and a connection for connecting the dozer blade to the dozer frame.

In off-the-road vehicles, such as bulldozers, scrapers, etc., utilizing dozer blades for dirt and debris movement, complete adjustability of the dozer blade renders the vehicle more versatile. These adjustments can be made by manually changing the blade position but for convenience as well as for timesaving purposes, appropriate motors that can be controlled from the operators seat are preferred. It is also preferable that the number of motors and controls be a minimum to avoid complexity and cost.

With the foregoing in mind, a new and different control system is contemplated for obtaining a dozer blade pitch adjustment.

Further contemplated is a dozer blade control system that is operable from the seat of the vehicle that combines with the tilt control for the blade tilt motors and the control for other blade adjusting motors to change the pitch of the blade.

Still further contemplated is a mechanism for connecting the dozer blade to the dozer frame.

The foregoing and other objects and advantages of the invention will become apparent from the following description and the accompanying drawings, in which:

FIG. 1 is a side elevational view of a crawler tractor on which a dozer blade is arranged for adjustment about plural axes;

FIG. 2 is a schematic illustration of a dozer blade control system incorporating the principles of the invention;

FIG. 3 is a plan view of the ball and socket connection joining the dozer blade to the crawler tractor frame;

FIG. 4 is an elevation view, partially in cross section, through the line 44 of FIG. 3;

FIG. 5 is an elevation view, partially in cross section, of an alternate embodiment of the connection shown in FIG. 3; and

FIG. 6 is an elevation view, partially in cross section, of another alternate embodiment of the connection shown in FIG. 3.

Referring first to FIG. 1, the numeral 10 denotes a bulldozer to which a C-shaped frame 12 is pivotally connected. The pivotal connections of the C-shaped frame 12 are at the junc tions 14 on each side of the bulldozer 10. A dozer blade 16 having a plate 18 welded to the backside thereof is suitably swivelly connected to the C-shaped frame 12, e.g., by a ball and socket connection 20 to be described in detail hereinafter. The ball and socket connection 20 connects to the longitudinal axis of the bulldozer 10. By this ball and socket connection 20, the blade 16 can be rotated or tilted about the longitu dinal axis of the bulldozer 10 so as to raise and lower respective ends of the blade 16, or pivoted about an axis which is vertical relative to the longitudinal axis of the bulldozer 10. Also, the blade 16 can be pitched forward or backward about a horizontal axis that is perpendicular to the bulldozers longitudinal axis so that the top of the blade 16 is either moved forward or backward relative to its bottom.

The C-shaped frame 12 can be raised and lowered, and accordingly the dozer blade 16 about the junctions 14, by a pair of lift motors 22 positioned on opposite sides of the bulldozer 10. These lift motors 22 are of piston type, each having a cylinder 24 connected to the side of the bulldozer 10 by trunnion 26 and a piston and rod assembly 28 that is connected by a universal connection 30 or the C-shaped frame 12.

The pivoting of the dozer blade 16 about a vertical axis defined by the connection 18 so as to change the angle of the dozer blade 16 is the function of a pair of oppositely acting angle motors 32, one on each side of the bulldozer 10. Each of these angle motors 32 includes a cylinder 34 which is appropriately anchored to the bulldozer 10 and a piston and rod assembly 36, which is connected by a ball and socket'connection at 38 to a strut 40. The strut 40 is joined by a universal connection 41 to the bottom of the dozer blade 16. Tilt motors 42 connect the strut 40 to the top of the dozer blade 16 and this is done by a tilt motor cylinder 43 which is secured by a ball and socket connection 44 to the strut 40 and a tilt motor piston and rod assembly 45 which is connected by a universal connection 46 to the top of the dozer blade 16.

The details of much of the foregoing described structure can be found in the U.S. Pat. to Long, No. 2,943,407.

Referring now to FIG. 2, the hydraulic circuitry illustrated has pressure fluid source, such as a pump 48 with its inlet 50 connected to a reservoir 52. The pump 48, when operative, supplies fluid under pressure to its outlet denoted generally at 54.

Connected to this outlet 54 is a manually operable tilt control valve shown generally at 56. This tilt control valve 56 is adjustable to connect the outlet 54 either to a supply line 58 or to a supply line 60 extending to the respective head ends of the tilt motors 42. The rod ends of the motors 42 are connected by an interconnecting line 62. Thus, the tilt motor control valve 56 can be adjusted to supply pressure fluid by way of supply line 58 while connecting the other supply line 60 to the reservoir 52 by way of a discharge line 64. Consequently, the tilt motor 42 to which pressure fluid is supplied, has its piston and rod assembly 45 extended. When extended, the fluid in its rod end is forced into the rod end of the opposite motor 42 and to retract its piston and rod assembly 45. As explained, this opposite motor action tilts the blade 16.

The tilt motor control valve 56 can also be moved to its neutral setting and disconnect the supply lines 58 and 60 from both the pump outlet 54 and the discharge line 64.

A manually adjustable lift motor control valve shown generally at 66, connects the pump outlet 54 either to a supply line 68 extending to the head ends of the lift motors 22 so as to lower the dozer blade 16 or to the rod ends by way of a supply line 70 to raise the dozer blade 16. When the head ends of the lift motors 22 are supplied with pressure fluid, their rod ends are connected by the lift motor control valve 66 to the discharge line 64. Of course, when the rod ends are pressurized, the head ends are connected by the lift motor control valve 66 to the discharge line 64. In the neutral setting of the lift motor control valve 66, connection between the lift motors 22 and the pump 48 is disrupted. In so-called float position, the control valve 66 connects both the rod ends and the head ends of the lift motors 22 to the discharge line 64 and blocks or cuts off the communication with a pump outlet 54.

The angle motors 34 are controlled by an angle motor control valve 72 which is manually operable to connect the pump outlet 54 either to a supply line 74 or a supply line 76. These supply lines 74 and 76 extend respectively to the rod end of one of the motors 32 and the head end of the other so that whichever one of the supply lines 74 or 76 not supplied with pressure fluid is connected by the angle motor control valve 72 to the discharge line 644. Consequently, the angle motors 32 are oppositely acting and the piston and rod assembly 36 force is extended and while the other is retracted to adjust the angle of the dozer blade 16 relative to the vertical axis defined by the connection 20.

Completing the circuitry is a manually operable selector valve 78 of the on-off or open-closed type. The selector valve 78 is connected by a line 80 to the interconnecting line 62 between the rod ends of the tilt motors 42, and a line 82 leading to the cylinders 24 and valve 66.

When, for example, the lines 80 and 82 are connected, any reduction in the fluid in the rod ends of the tilt motors 42 due to leakage can be replaced or supplemented to maintain the settings of the tilt motors 46 whenever the supply line 82 is pressurized.

Also, the selector valve 78 can be utilized to operate the tilt motors so as to change the pitch of the dozer blade 16. One way of accomplishing this is to maneuver the lift motor control valve 66 so that each of the rod ends of the lift motors 22 is supplied with pressure fluid and each of the head ends is connected to the discharge line 64. This will actuate the lift motors 22 to raise the dozer blade 16 to its full height. With the supply line 70 still pressurized, (fluid being forced over the main relief) the selector valve 78 is changed to the open setting so as to connect the lines 80 and 82 and transfer this pressurized fluid in the supply line 70 to the interconnecting line 62 and to the rod ends of both of the tilt motors 42 to facilitate their reaction. Now by alternate operation of the tilt motor control valve 56, each of the tilt motors 42 is adjusted so that the piston and rod assemblies 45 are both retracted to move the top of the dozer blade 16 rearwardly or pitch the dozer blade 16 backwardly its maximum extent. The selector valve 78 is then returned to its closed setting disconnecting the lines 80 and 82.

The lift motor control valve 66 can be positioned in its neutral setting or adjusted so that the supply line 68 is pressurized and the blade 16 lowered for operation at the maximum pitch. The bulldozer 10 can be operated so as to lift, dig and angle right or left in this pitched position. The 'dozer blade 16 canhot be tilted with both piston and rod assemblies retracted.

To pitch the dozer blade 16 forwardly, the dozer blade 16 is lowered to the ground by adjusting the lift motor control valve 66 so that the supply line 68 to the head ends is supplied with pressurized fluid and the supply line 70 to the rod ends is connected to the discharge line 64. With the dozer blade 16 lowered and in engagement with the ground, the lift motor control valve 66 is placed in the float setting blocking communication between the line 70 and the pump outlet 54 while connecting supply lines 68 and 70 to the discharge line 64. The selector valve 78 is next placed in the open setting to connect the supply line 70 and to the interconnecting line 62 to the rod ends of the tilt motors 42. The tilt motor control valve 56 is then operated to energize one of the supply lines 58 or 60, for example, the supply line 60, to extend the corresponding piston and rod assembly 45. Only the one tilt motor 42 is operated to move the dozer blade 16 to a midpitch position. With the selector valve 78 open, the usual pressure build up in the one rod end of the tilt motor 42 being extended and transferred by the interconnecting line 62 to the other tilt motor rod end is not possible because the interconnecting line 62 is connected to the supply line 70 which is connected to the reservoir 52. Thus, any tendency for a pressure buildup, which would otherwise provide the opposite motor action, is returned to the reservoir 52.

To pitch the dozer blade 16 forwardly its maximum extent, the lift motor control valve 66 is positioned as before so that the blade 16 is lowered into engagement with the ground and then placed in the float setting with the supply line 70 disconnected from the pump 48 and connected to the reservoir 52. The selector valve 78 is opened to connect the lines 80 and 82 and as the tilt motor control valve 56 alternately operated to extend each of the piston and rod assemblies 45 of the tilt motors 42. The fluid in the interconnecting line 62 cannot become'pressurized by this alternate operation because it is returned to the reservoir by way of the line 70. Now the selector valve 78 is closed. Disconnecting the lines 80 and 82, the blade 16 is pitched forward.

The foregoing sequence of events can be accomplished by alternatively using the circuitry to the angle motors 32. This connection of the line 82 to the supply line 74 to the angle motors 32 must, by operation of the angle motor control valve 72, be such that the fluid in the interconnecting line 62 is either pressurized or connected to the reservoir 52, when the selector valve 78 is opened to attain the foregoing pitch operation.

From the foregoing, it will be appreciated that the blade tilt motors 42 can be now utilized to change blade pitch thereby affording another blade adjustment with existing structures and with a minimum number of additional components.

The ball and socket connection 20 (see FIGS. 3, 4, and 6) comprises a horizontally positioned upper ear 84 and a lower ear 86' opposed from each other and projecting from the center of the C-frame 12. Each car 84 and 86 has a vertical bore 88 which is axially aligned with the bore in the opposed ear. An arcuate plate 90 is vertically mounted between the ears 84 and 86, and the cars 84 and 86 combined with the arcuate plate 90 definea space.

An ear 92 is welded to the plate 18 on the backside of the dozer blade 16. The car 92 has a vertical bore 94 which, when the ear 92 is in position between the ears 84 and 86, is axially aligned with the bore 88 in the cars 84 and 86 projecting from the C-frame 12. In the embodiment shown in FIG. 4, the bore 94 in the ear 92 has an outwardly flared section 96 at the top, an enlarged diameter middle section 98, and a still greater enlarged diameter internally threaded section 100 at the bottom. A swivel pin 102 having a square pinhead 104 is inserted through the bores 88 in the ears 84 and 86 and the bore 94 in ear 92 attached to the bulldozer blade 16 and is secured by a hex-nut 106 tightened against a thrust washer 108 abutting the top surface of the car 84. The hex-nut 106 is held on by cotter pin 1 10.

A swivel ball 112 is mounted on the pin 102 and is spaced from the ears 84 and 86 by cone spacers 114 on the top and bottom sides thereof. An outer race 116 is mounted in the enlarged diameter middle section 98 of the bore 94 and its inner shape is complementary to that of the swivel ball 112. A retainer 118 threaded into the internally threaded section 100 of the bore 94 retains the race 116 in position. The inner periphery of the retainer 118 is outwardly flared at an angle identical to the flared section 96.

A pin stop 120 is mounted on the underneath side of the ear 82 to prevent rotation of the pin 102.

The arrangement of the swivel ball 112 allows the rotation of the bulldozer blade 16 about a horizontal and vertical axis within the ball and socket connection 20. The vertical axis is the axis of the pin 102 and the horizontal axis is the axis of the ball 112.

In an alternative embodiment, as shown in FIG. 5, bore 94 is cylindrical and the outer race 116 is held in place by means of retaining rings 122 inserted in the annular recesses in the bore 94 in the ear, one on each side of the outer race 116.

In still another embodiment, as shown in FIG. 6, the bore 94 has an outwardly flared upper section 124 and an enlarged diameter lower section 126 having an annular groove 128. A shoulder 130 is formed between the upper section 124 and the lower section 128. The race 112 is secured in podtion between the shoulder 130 and a retaining ring 132 in the annular groove 128.

What is claimed is:

1. A control system for adjusting a vehicle dozer blade comprising a source of pressure fluid, and a pair of double-acting tilt motors operatively connected to the blade for rotating the blade about the longitudinal axis of the vehicle to vary the blade tilt, the tilt motors each having an operating end thereof, connected to the source and the opposite end thereof in fluid communication with the corresponding end of the other tilt motor, tilt motor control valve means selectively operative to separately connect the operating end of one of the tilt motors to the source and to discharge the operating end of the other tilt motor so as to cause the tilt motors to rotate the blade about the longitudinal axis of the vehicle, a pair of blade adjusting motors operatively connected to the blade for maneuvering the blade about another axis of the vehicle, blade adjusting motor valve control means selectively operative to connect and disconnect the pair of blade adjusting motors to and from the source so as to cause the blade to be maneuvered about the other axis of the vehicle, and manually operable valve means in fluid communication with the opposite ends of the tilt motors, the pair of blade adjusting motors and the blade adjusting motor control valve means for selectively connecting the opposite ends of the tilt motors to the source by way of the blade adjusting motor valve control means so that the fluid to the opposite ends of the tilt motors can be pressurized or relieved when the blade adjusting motor control means is operated and the pitch of the blade varied by operation of the tilt motors by the tilt motor control means.

2. The control system described in claim 1, wherein the pair of blade adjusting motors raise and lower the blade about an axis that is transverse to the vehicle longitudinal axis.

3. A'control system for adjusting a vehicle dozer blade comprising a source of pressure fluid, a pair of tilt motors of the piston type operatively connected to the blade, for rotating the blade about a longitudinal axis of the vehicle, the tilt motors each having the rod ends thereof in fluid communication and the head ends thereof arranged to be connected separately to the source, tilt motor control valve means selectively operative to separately connect the head end of one of the tilt motors to the source and to discharge the head end of the other tilt motor so as to cause the blade to be tilted, a pair of blade-adjusting motors operatively connected to the blade for maneuvering the blade about another axis of the vehicle, blade adjusting motor control valve means for selectively connecting the pair of blade-adjusting motors to the source for rendering the blade-adjusting motors operative, manually operable valve means in fluid communication with the opposite ends of the tilt motors, the pair of blade adjusting motors and the blade-adjusting motor control valve means for selectively connecting the rod ends of the tilt motors to the source by way of the blade-adjusting motor control valve means so that the fluid to the rod ends of the tilt motors can either be pressurized or relieved by operation of the blade-adjusting motor control valve means and thereby enable the tilt motors to be operated by the tilt motor control valve means to vary the pitch of the blade.

4. A control system for adjusting a vehicle dozer blade about a plurality of axes comprising a source of pressure fluid, a pair of tilt motors of the piston type operatively connected to the blade for rotating the blade about the longitudinal axis of the vehicle, the tilt motors each having the rod ends in fluid communication and the head ends thereof arranged to be separately connected to the source, tilt motor control valve means selectively operative to connect the head end of one of the tilt motors to the source and to discharge the head end of the other tilt motor so as to cause the tilt motors to tilt the blade, a pair of lift motors operatively connected to the blade for raising and lowering the blade, control valve means for lifting motors, and manually operable valve means for connecting the rod ends of the tilt motors to the control valve means so that fluid in the rod ends of the tilt motors can either be pressurized or relieved by operation of the control valve means and thereby enable the tilt motors to be operated by the tilt motor control valve means to vary the pitch of the blade.

5. The control system of claim 1 which further includes a connection between said blade and the frame of said vehicle comprising a pair of opposed ears projecting from one of said frame or said blade having vertically axially aligned bores therein, a third ear projecting either from the other of said frame or said blade positioned between said opposed ears and having a bore therein which is axially aligned with said bores in said opposed ears, a swivel pin extending through said bores, said pin secured in position, a swivel ball mounted around said pin between said opposed ears and within said bore in said third ear and spaced from said opposed ears by spacing means, an outer race mounted in said bore of said third ear for said swivel ball, and means securing said race in position, whereby said blade is capable of movement around a horizontal and vertical axis. 

1. A control system for adjusting a vehicle dozer blade comprising a source of pressure fluid, and a pair of doubleacting tilt motors operatively connected to the blade for rotating the blade about the longitudinal axis of the vehicle to vary the blade tilt, the tilt motors each having an operating end thereof, connected to the source and the opposite end thereof in fluid communication with the corresponding end of the other tilt motor, tilt motor control valve means selectively operative to separately connect the operating end of one of the tilt motors to the source and to discharge the operating end of the other tilt motor so as to cause the tilt motors to rotate the blade about the longitudinal axis of the vehicle, a pair of blade adjusting motors operatively connected to the blade for maneuvering the blade about another axis of the vehicle, blade adjusting motor valve control means selectively operative to connect and disconnect the pair of blade adjusting motors to and from the source so as to cause the blade to be maneuvered about the other axis of the vehicle, and manually operable valve means in fluid communication with the opposite ends of the tilt motors, the pair of blade adjusting motors and the blade adjusting motor control valve means for selectively connecting the opposite ends of the tilt motors to the source by way of the blade adjusting motor valve control means so that the fluid to the opposite ends of the tilt motors can be pressurized or relieved when the blade adjusting motor control means is operated and the pitch of the blade varied by operation of the tilt motors by the tilt motor control means.
 2. The control system described in claim 1, wherein the pair of blade adjusting motors raise and lower the blade about an axis that is transverse to the vehicle longitudinal axis.
 3. A control system for adjusting a vehicle dozer blade comprising a source of pressure fluid, a pair of tilt motors of the piston type operatively connected to the blade, for rotating the blade about a longitudinal axis of the vehicle, the tilt motors each having the rod ends thereof in fluid communication and the head ends thereof arranged to be connected separately to the source, tilt motor control valve means selectively operative to separately connect the head end of one of the tilt motors to the source and to discharge the head end of the other tilt motor so as to cause the blade to be tilted, a pair of blade-adjusting motors operatively connected to the blade for maneuvering the blade about another axis of the vehicle, blade adjusting motor control valve means for selectively connecting the pair of blade-adjusting motors to the source for rendering the blade-adjusting motors operative, manually operable valve means in fluid communication with the opposite ends of the tilt motors, the pair of blade adjusting motors and the blade-adjusting motor control valve means for selectively connecting the rod ends of the tilt motors to the source by way of the blade-adjusting motor control valve means so that the fluid to the rod ends of the tilt motors can either be pressurized or relieved by operation of the blade-adjusting motor control valve means and thereby enable the tilt motors to be operated by the tilt motor control valve means to vary the pitch of the blade.
 4. A control system for adjusting a vehicle dozer blade about a plurality of axes comprising a source of pressure fluid, a pair of tilt motors of the piston type operatively connected to the blade for rotating the blade about the longitudinal axis of the vehicle, the tilt motors each having the rod ends in fluid communication and the head ends thereof arranged to be separately connected to the source, tilt motor control valve means selectively operative to connect the head end of one of the tilt motors to the source and to discharge the head end of the other tilt motor so as to cause the tilt motors to tilt the blade, a pair of lift motors operatively connected to the blade for raising and lowering thE blade, control valve means for lifting motors, and manually operable valve means for connecting the rod ends of the tilt motors to the control valve means so that fluid in the rod ends of the tilt motors can either be pressurized or relieved by operation of the control valve means and thereby enable the tilt motors to be operated by the tilt motor control valve means to vary the pitch of the blade.
 5. The control system of claim 1 which further includes a connection between said blade and the frame of said vehicle comprising a pair of opposed ears projecting from one of said frame or said blade having vertically axially aligned bores therein, a third ear projecting either from the other of said frame or said blade positioned between said opposed ears and having a bore therein which is axially aligned with said bores in said opposed ears, a swivel pin extending through said bores, said pin secured in position, a swivel ball mounted around said pin between said opposed ears and within said bore in said third ear and spaced from said opposed ears by spacing means, an outer race mounted in said bore of said third ear for said swivel ball, and means securing said race in position, whereby said blade is capable of movement around a horizontal and vertical axis. 